Preparation of fiber for paper-pulp



N. PETERS, PHDTQLITHOGRAPHER. WASHINGTON. D C,

N-FUERS, PHOT0-L THOGRAPHER WASHINGTON D C ENIT STATES PATENT OFFICE.

MARTIN NIXON, OF PHILADELPHIA, PENNSYLVANIA.

PREPARATION OF FIBER FOR PAPER-PULP.

To all whom it only concern.:

Be it known that I, MARTIN Nrxox, of Philadelphia, in the State ofPennsylvania, have invented a new and useful Improvement in theManufacture of Faper-Pulp from Straw and Like Substances; and I dohereby declare the following to be a full, clear, and exact descriptionthereof, reference being had to the annexed drawings, making part ofthis specification.

The prominent distinguishingfeature of this invention consists in amethod of boiling which involves less labor and results in a betteryield of pulp in quantity and quality than is attainable by any otherprocess known to me.

In the accompanying drawings Figures l, 2, and 6, exhibit inperspective, various modifications of my boiling tub. Fig. 3, is anaxial view of Fig. l. Figs. 4, and 5, exhibit two forms of thealkalizing nozzle or nose.

My process is asv follows: I put whole straw in its natural state into atub or tank a, provided with a perforated floor or false bottom b, onwhich the straw is supported. The space beneath the floor b, is filledwith an alkaline solution about 8 Baume' in strength, and in quantityfrom 30 to 35 gallons to every 100 lbs. of straw. The bottom angle ofthe tub beneath the floor 7;, is occupied by a steam pipe c, perforatedat intervals of about two feetwith apertures about one eighth of an inchin diameter to permit the escape of jets of steam toward the center ofthe tub.

(l, is a perforated cover which rests on the mass of straw.

lf) J c, is a pipe extending axially from beneath the floor 7). to ashort distance above the cover d, where it may be surmounted with aninverted bowl f, or with a centrifugal spreader or rose g, but when thelatter is used the cover CZ. may be dispensed with.

7i., is a draw off cock, of which there may be one or more in thebott-0m of each tub.

27, is a pipe discharging a current of steam into the mouth of the axialpipe c, which serves to impel a portion of the alkaline solution upwardthrough said pipe and deliver it in a heated state in a continuousspreading shower upon the top of the straw (or upon the perforated coverwhere one is used) from whence it percolates downward through the massof straw. At the same time the steam which escapes into the spacebeneath the iieor rises through the straw. Thus there are constantlypassing through the straw a descending stream of hot alkaline solutionand an ascending volume of steam.

The following are among the advantages resulting from the abovedescribed method of boiling.

1st. The mass of straw is preserved in a light and porous condition,free from needless matting and bruising, enabling the deglutenizingagent to circulate freely throughout without being unduly retained inany part. The knotty portions of the straw are thus eectually reduced soas to prevent the existence of yellow pimples and specks which so oftendeface straw paper; and at the same time the extensive waste of thefiner portions of the liber, incident to severe and repeated washingsand stirrings during the deglutenizing process is avoided.

2nd. The condensation of steam causes the alkaline solution to decreasein strength as the work of disintegration progresses.

3rd. A vast amount of laborious and costly manipulation is avoided.

4th. The chemical agents are economized to the greatest possible extent.

For reasons above stated it is my aim to avoid cutting or bruising thestraw before the 'close of the alkaline treatment, preferring to keep itas nearly as possible in its natural form until the washing out of thealkali. The charge of straw for a tub ten feet in diameter and eightfeet deep is about four thousand pounds. The deglutenizing process underordinary circumstances occupies about twelve hours.

When the straw is cooked I drain off the liquor. and employ it to breakdown a new batch of straw in another tub. I'then run in upon the strawin the first tub a stream of cold water, to wash out the alkali, glutenttc., and to cool the straw. I then .transfer the straw into a straw orrag washer and then into a rag engine; or direct into the engine, whereit is washed thoroughly by the action of the roll and cylinder washerunt-il the'water runs clear therefrom. I then put in about l lb. oilvitriol to the 100 lbs. straw and let it mix well with the fiber, whichunder the action of the roll takes about live minutes, and then washout. I then let down the roll and open the straw into lint or fiber Theengine is then again washed down, and afterward clear bleach liquor isdrawn in from a reservoir, unt-il all the water in the engine is ofproper strength to bleach, the strength used by me being o to lo Iauinaccor-fling to the grade of back news or writing paper for which thestock is intended, using for fair newspaper about l-O Baume.

From the engine the stock may be let down into bleach boxes or vats; orthe washed and iibered straw may be let down into drainers and drainedand then brought back and put into bleach liquor in the engine andafterward let down into bleach 4 boxes or vats; or it may be washed andopened into iber in the engine and let down into vats containing bleachliquor. I have operated it in diilerent ways but prefer the mode firstdescribed of applying the bleach liquor in the engine. The bleachingbeing accomplished the stock may be worked up in the usual way for halfstuff.

Pulp made by the above process, works well in any proportion with ragstock, and I make an excellent tough and white paper of straw only. Ialso manufacture by my process-omitting the bleach-a tough article ofpaper having the natural Color of the straw.

I am aware that a process has existed, whereby the alkaline solution, isby the agency of steam, heated in a separate vessel and delivered on topof the straw in intermittent showers. This I do not claim, neither do Iclaim any process in which cutting of the straw is a prerequisite; but

I claim as new and of my inventionl. The described manner of applyingthe steam, whereby the solution is automatically and continuouslydelivered on top of the straw as set forth.

2. The process of boiling whole straw by the combined action of anupward current of steam and a downward current of alkaline solutionpermeating the mass and acting upon it in conjunction substantially inthe manner and for the purpose explained.

In testimony of which invention I hereunto set my hand.

MARTIN NIXON.

Attest:

GEO. H. KNIGHT, JAS. I-I. GRIDLY.

